They'll fit on the stock 7" wide rim, but they're pretty much maxed out. Nice and fat though! I have the 275/50's which are pretty popular. No problems at all on my stock GN wheels. I am, however, going to 15x8" rims for the rear when I obtain my centerlines.

IMO, the 275/60/15, or 275/50/15's on stock width rims are a bit too wide depending on tire brand, and the aspect ratio on a tire/rim combo like that causes the tread to crown, causing uneven wear in the center section. The tire may be fatter, but I doubt you get batter traction when compared to a properly matched tire/rim width.

I upgraded to 8.5 inch rims, with 275/60/15 tires recently, and am happy with both the way they look, and with the tire wear looking normal. The tread on the tire is wearing evenly, as opposed to what it was doing with the narrower rim, even with the narrower 255 tire. A lot depends on the tire brand, some just seem wider when mounted even though they say they are a certain size.

I've seen pics of guys with 295/50's on the stock 7 inch rim, and it just doesn't look right, with all of that sidewall just bulging out from the rim.